I’ve never quite understood the whole coaster thing; perhaps because I eat dinner at my coffee table where there are no rules as to what can be placed atop, or because I love my linen cocktail napkins. So really what it comes down to is that I have never had a need for a coaster set. But then I saw these referred to as trivets and that was something I could understand. And what perfect timing as my guy and I were just talking about looking for a trivet. This is probably not what he had in mind but perhaps I can sneak a couple into the kitchen anyway. They range between 5-6″ so as a single it’s perfect for my teapot or his Chemex coffee, or for larger pieces a few of them might be needed. From Leif $20 each.